New lozenge aims to ease radiation mouth sores for hours

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Participant must provide signed written informed consent prior to trial participation and must be willing and able to comply with all requirements and restrictions of the trial. * Male or female aged ≥ 18 on the day of consent and ≤ 80 on the first day of dosing. * Pathologically confirmed diagnosis of squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or nasopharynx. * About to start IMRT with curative intent with daily fractions of 2.0 Gy to 2.2 Gy to a cumulative intended dose of at least 60 Gy and a maximum of 72 Gy. Proton therapy given at equivalent biological doses is allowed. * Eastern Cooperative Oncology Group (ECOG) Performance Status 0-2. * Female participants of childbearing potential (WOCBP) must agree to use a highly effective contraceptive measure or practice total sexual abstinence from the time of giving informed consent until at least 24 hours after last dose of IMP. Exclusion Criteria: * Participation in another investigational interventional clinical trial within 3 months prior to first dosing, or for a longer period if required by local regulations, or within 5 half-lives of the investigational agent taken (whichever is longer). An exception is studies where patients are randomized to different radiotherapy settings, e.g. participation in DAHANCA 35 is allowed. * Previous radiation therapy to the head and/or neck area. * Pre-existing OM, active herpes simplex virus (HSV) infection, or untreated or uncontrolled oral candidiasis. * Receiving high-dose (\> 15 mg per day prednisolone), corticosteroids (for any indication). * Known allergy or intolerance to bupivacaine, lidocaine, or any of the excipients in the products. * Significant cardiac disease such as AV block II-III or requiring treatment with antiarrhythmic drugs in class III (e.g., amiodarone). * Inability to eat or drink, or dependence on an enteral feeding tube (percutaneous endoscopic gastrostomy \[PEG\] or nasogastric tube) for any reason. * Moderate/severe liver or kidney disease defined as: 1. AST/ALT \> 3 × upper limit of normal (ULN) or bilirubin \> 1.5 × ULN (unless related to Gilbert's syndrome) 2. glomerular filtration rate (GFR) \< 30 mL/min/1.73 m2 * Known diagnosis of epilepsy. * Known phenylketonuria (PKU). * Pregnancy or breastfeeding. * Any condition or circumstance-based on the investigator's assessment-that could increase risk to the participant, confound trial results, or interfere with compliance / participation (including inability or unwillingness to follow trial procedures, or any clinically significant physical or psychiatric condition).